Looks like you have qualified restoration people working there and they understand the nature of the building. I've had the misfortune of having seen several really bad attempts to "restore" older religious buildings and I can only ask every member of the forum who might ever be in the position to commission any restoration work on any building to please be sure that they're working with qualified people...amateurs need not apply.

Recently my own uncle, in a very well intentioned effort to restore his local church, removed some murals from the sections of a dome surrounding an altar in a Roman Catholic church and only then asked my wife, who's an authority on this sort of thing, if they should have been taken down. You ever get that awful drop-out feeling in the pit of your stomach?

Please keep us posted on the progress of the work.

Best

AA